Much of the new development in Los Angeles and Orange counties is occurring on land the state says is at high risk for wildfires, according to records and interviews.
With little raw land available in flat areas, builders are planning huge tracts of homes on or just below the rough hillsides that fringe the region's metropolitan areas.
Hillside living is popular with home buyers because of the sweeping views, country feel and proximity to nature. But with their tall brush and trees, and steep terrain that can act as a wind tunnel to speed along a blaze, these are the very areas likely to burn.
A symbol of how the suburban building boom has stretched to meet the fire danger can be found off Plum Canyon Road near Canyon Country, where last month's fires blackened land being graded for new homes. The fire left the distorted remains of water sprinklers coated with ash and dirt.
But no sooner had the flames died than construction workers were back out, cleaning the site in unincorporated Santa Clarita and preparing to build 600 homes.
The project, called Monte Verde, is in what L.A. County planners and fire officials call a "very high fire hazard severity zone," the riskiest designation.
In the wake of the October blazes that burned more than 2,000 homes, Gov. Arnold Schwarzenegger asked a state wildfire task force to consider whether construction should be limited in the riskiest zones, joining a growing chorus of safety advocates and environmentalists who have also proposed tougher hillside building rules.
Despite such concerns, however, a tide of new development in high-risk zones is well underway.
About 60,000 new homes are proposed for the hills, canyons and scrubby flats of northern Los Angeles County over the next few years.
These include two mega- developments along what is now a sparsely populated stretch of the 5 Freeway: Centennial, near Tejon Ranch; and Newhall Ranch, north of Santa Clarita.
In Orange County, more than 20,000 homes are planned by the Irvine Co. and Mission Viejo Co. in zones considered at high risk for brush fires.
Fire prevention officials say they require homes built in such areas to include a long list of safety features, including landscaping meant to keep flames away from houses and the use of flame-retardant building materials. They note these are precautions that newer communities, including Foothill Ranch, Portola Hills and Stevenson Ranch, have taken to protect homes.
Michael LeBlanc of the Irvine Co. said he watched with some satisfaction last month as news reports showed the Santiago fire racing across a toll road and around a bend toward the first phase of the firm's 4,500-home Portola Springs project, and then dying.
"It reached the fuel modification zone and it stopped," he said. "The fire just stopped."
But some longtime safety advocates say building in fire zones puts people at risk and costs society billions for firefighting and rescue efforts.
"This is a land rush into danger," said Roger Kennedy, former director of the National Park Service and author of a recent book on wildfires. "A land rush by people who do not understand what they are doing and who are subsidized by others to do it. It's crazy."
Even if firefighters can save these homes, the firefighting costs are expected to continue to rise.
The state legislative analyst's office estimated that it would cost about $869 million to fight wildfires in fiscal 2007-08 -- an 83% increase over the cost 10 years ago.
In a report released earlier this year, the legislative analyst recommended that local governments that approve development in high-risk fire zones be required to pay for the cost of firefighting. Homeowners should also pay an extra firefighting fee if they choose to move to such areas, the report recommended.
Schwarzenegger last week asked the blue-ribbon commission set up after the 2003 wildfires to reexamine rules for building in high-severity fire zones, although a spokesman said it was too soon to say what changes might be needed.
Public agencies and the politicians who run them have long been wary of telling property owners they cannot build somewhere simply because of fire risk.
But Carroll Wills, a spokesman for the California Professional Firefighters union, said that fires in recent years have become more frequent -- and ferocious. In four years, he said, the state has suffered two fires that are normally considered "100-year" events -- the October fires and those in 2003.
"A fire like we had this time . . . aside from building your home out of solid marble, you're not going to stop that fire," Wills said.
Among the other L.A. County developments in high-risk areas are Newhall Ranch, Las Lomas, Centennial and Ritter Ranch, according to fire experts, county planners, developers and state and local fire maps. The Anaverde project in the Palmdale area borders such a zone.